Multiple blade hacksaw



Oct. 12, 1948. T. DONNELLY 2,450,942

' MULTIPLE BLADE HACKSAW Filed March 8, 1946 INVENTOR. THOMAS DONNELLY,

Ea; l.

ATTORNEYS.

Patented Oct. 12, 1948 UNITED STATES ATENT FFlCE Y I 2,450,942 1 MULTIPLE BLADE. H-AGKSAW Thomas Dbnnelly, Wilmington, Calif. Application March 8, 1946 S erialNo 653,097

This invention relates to hacksaws, and more particularly to a hacksaw employing multiple blades.

A main object of the invention is to provide a novel and improved h-acksaw'structure wherein a plurality of blades may be simultaneously mounted for obtaining multiple cutting action of the saw.

A further object of the invention is to provide an improved hacksaw structure wherein two 2 Claims. (01. 145-41)" blades may be accommodated, one of the blades serving as a guide to insure constant thickness of the portion being cut off by the other lblade.

A still further object of the invention is to provide an improved hacksaw structure wherein the blade may be positioned in any one of a plurality of laterally offset positions with respect to the axis of the saw frame whereby operation of the saw in close quarters will be facilitated.

Further objects and advantages of the inven tion will become apparent from the following description and claims, and from the accompanying drawing, wherein:

Figure 1 is an elevational View of a hacksaw constructed in accordance with the present invention.

Figure 2 is a detail elevational view of a tensioning bolt member employed in the 'hacksaw structure of Figure 1, showing the end portions of a plurality of hacksaw blades engaged therewith.

Figure 3 is a cross-sectional view taken onl-ine 3-3 of Figure 2.

Figure 4 is :a top plan view of the structure of Figure 2.

Referring to the drawing, I I designates a conventional hacksaw frame having a first section l2 provided with a handle l3, and a second section l4 telescopically engaging the first section I2 for longitudinal adjustment thereon in a well known manner. Rigidly secured to the first section is a leg member l5 carrying a loop element l6 for receiving a first hacksaw retaining bolt, second section l4 being provided with a leg member ll carrying a loop element l8 aligned with loop element l6 for receiving a hacksaw tensioning bolt. The structure thus far described is conventional and forms no part of the present invention.

' A bolt member I9 is formed with a threaded free end portion which is extended through said loop l6 toward said handle. Such threaded portion of the :bolt is adapted to receive a tensionresisting nut l9 which engages the handle side of the loop element IE to prevent withdrawal of said bolt in the opposite direction. The shank portion of bolt member I9 is formed on each side with a plurality of stepped sections 20, 2| and 22, there being three such sections shown herein but any desired number of sections being contemplated within the spirit of the invention. The inner section 20 is of least thickness, the next section 2| of greater thickness and the last section 22 of greatest thickness. Each section is provided with a pair of laterally projecting hacksaw engaging pins symmetrically located thereon.

Engaged in loop element I8 is a tensioning bolt member 323 whose outer portion is threaded to receive a conventional tensioning wing nut 24 and whose shank portion is similar in all respects to the shank portion of bolt member 19, there being a plurality of stepped sections 25, 26 and 21 of graduated thickness whose side surfaces are respectively aligned with the side surfaces of stepped sections 20, 2| and 22- of bolt member l9. Each of the stepped sections 25, 26 and 21 is provided with'a pair of laterally projecting hacksaw engaging pins symmetrically disposed thereon.

A hacksaw blade 28 may be secured in frame I l by engagement with the pins carried by sections 20 and 2'5, 2! and 2-6 or =22 and 21 on either side 'of the plane of frame II. This provides a range of six different ofiset positions of the blade with respect to the plane of the frame, where only one blade is employed, enabling the operator to set the blade in the best position on the frame for a particular job. This is highly advantageous, especially when working in close quarters.

Alternatively, a pair of symmetrically mounted blades may be employed in the frame H to provide a double out where desired, or one of the blades may be employed as a guide for insuring constant thickness of out where it is desired to remove a slice of constant known thickness from the end of a bar or other object.

Finally, a plurality of pairs of symmetrically mounted blades may be employed in frame I l as shown by way of illustration in Figures 2, 3 and 4, to obtain a multiple saw' cut, such as multiple grooves of accurate and constant spacing in a work piece.

Although described above in connection with a hand tool, the hack-saw blade engaging bolt members l9 and 23 may be similarly employed in a power saw frame.

While a specific embodiment of a hacksaw structure has been disclosed in the foregoing description, it will be understood that various modifi-cations within the spirit of the invention may occur to those skilled in the art. Therefore it is 3 intended that 'no limitations be placed on the invention other than as defined by the scope of the appended claims.

What is claimed is:

1. Blade-holding and tensioning means for a 'hacksaw, comprising a pair of bolts, means for supporting and tensioning said bolts, each bolt having a shank including outer side faces and a free end, at least one of said faces comprising a plurality of inwardly offset stepped portions toward said free end, and means on each stepped portion for detachably connecting a ha-cksaw blade thereto.

2. Blade-holding and tensioning means for a hacksaw, comprising a pair of bolts, each bolt having a shank including opposed outer side faces and a free end, both of said side faces comprising a. plurality of inwardly ofiset stepped portions toward said free end, and means on each stepped portion for detachably connecting a ha-cksaw blade thereto, means mounting said bolts in longitudinally spaced relation with corresponding stepped portions opposed and aligned, means for tensioning said bolts, said means on each pair of aligned stepped portions of said bolts being each adapted to support a blade 'of difierent length. THOMAS DONNELLY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 764,374 Remsen July 5, 1904 2,085,667 Macomber June 29, 1937 FOREIGN PATENTS Number Country Date 260,787 Italy Oct. 15, 1928 

